The present invention relates to combinations of taxol, Taxotere and their analogues and substances which are therapeutically useful in the treatment of neoplastic diseases.
Taxol, Taxotere and their analogues, which possess noteworthy antitumor and antileukemic properties, are especially useful in the treatment of cancers of the colon, ovary, breast or lung.
The preparation of taxol, Taxotere and their derivatives form the subject, for example, of European Patents EP 0,253,738 and EP 0,253,739 and International Application PCT WO 92/09,589.
Generally, the doses used, which depend on factors distinctive to the subject to be treated, are between 1 and 10 mg/kg administered intraperitoneally or between 1 and 3 mg/kg administered intravenously.
It has now been found, and this forms the subject of the present invention, that the efficacy of taxol, Taxotere and their analogues may be considerably improved when they are administered in combination with at least one substance which is therapeutically useful in anticancer treatments and has a mechanism identical to or different from this of taxane derivatives.
Among substances which may be used in association or in combination with taxol, Taxotere or their analogues, there may be mentioned alkylating agents such as cyclophosphamide, isosfamide, melphalan, hexametyl-melamine, thiotepa or dacarbazine, antimetabolites such as pyrimidine analogues, for instance 5-fluarouracil and cytarabine, or its analogues such as 2-flourodeoxycytidine, or folic acid analogues such as methotrexate, idatrexate or trimetrexate, spindle poisons including vinca alkaloids such as vinblastine or vincristine or their synthetic analogues such as navelbine, or estramustine or taxoids, epidophylloptoxins such as etoposide or teniposide, antibiotics such as daunorubicine, doxorubicin, bleomycin or mitomycin, enzymes such as L-asparaginase, topoisomerase inhibitors such as camptothecin derivatives chosen from CPT-11 and topotecan or pyridobenzoindole derivatives, and various agents such as procarbazine, mitoxantrone, platinum coordination complexes such as cisplatin or carboplatin, and biological response modifiers or growth factor inhibitors such as interferons or interleukins.
Moreover, since the activity of the products depends on the doses used, it is possible to use higher doses and to increase the activity while decreasing the toxicity phenomena or delaying their onset by combining growth factors of the haematopoietic type such as G-CSF or GM-CSF or certain interleukins with taxol, Taxotere, their analogues or their combinations with other therapeutically active substances.
The combinations or associations according to the invention enable the phenomena of pleiotropic resistance or xe2x80x9cmulti-drug resistancexe2x80x9d to be avoided to delayed.
More especially, the invention relates to combinations of taxol, Taxotere and their analogues with vinca alkaloids, cyclophosphamide, 5-fluorouracil, doxorubicin, cisplatin, navelbine, camptothecin, and etoposide.
The improved efficacy of a combination according to the invention may be demonstrated by determination of the therapeutic synergy. A combination manifests therapeutic synergy if it is therapeutically superior to one or other of the constituents used at its optimum dose (T. H. Corbett et al., Cancer Treatment Reports, 66:1187 (1982)).
To demonstrate the efficacy of a combination, it may be necessary to compare the maximum tolerated dose of the combination with the maximum tolerated dose of each of the separate constituents in the study in question. This efficacy may be quantified, for example, by the log10 cells killed, which is determined according to the following formula:
log10 cells killed=Txe2x88x92C(days)/3.32xc3x97Td
in which Txe2x88x92C represents the time taken for the cells to grow, which is the mean time in days for the tumors of the treated group (T) and the tumors of the treated group (C) to have reached a predetermined value (1 g for example), and Td represents the time in days needed for the volume of the tumor to double in the control animals [T. H. Corbett et al., Cancer, 40, 2660-2680 (1977); F. M. Schabel et al., Cancer Drug Development, Part B, Methods in Cancer Research, 17, 3-51, New York, Academic Press Inc. (1979)]. A product is considered to be active if log10 cells killed is greater than or equal to 0.7. A product is considered to be very active if log10 cells killed is greater than 2.8.
The combination, used at its own maximum tolerated dose, in which each of the constituents will be present at a dose generally not exceeding its maximum tolerated dose, will manifest therapeutic synergy when the log10 cells killed is greater than the value of the log10 cells killed of the best constituent when it is administered alone.